For each chapter It takes about 2-4 hours tops to put together about 3-4 letter pages.
I don’t actively plan things out, really, I tend to keep the stories in my head, so I usually start out by reviewing the last chapter/letters and deciding how far things have come.
What takes a lot of time is the research.
Since it’s set during specific years/dates, it’s important to know key events, food, terminology, technology, sometimes clothing, etc.
I also looked into the homes they would have, selected specific mansions on both California and London. So if you look up the addresses on the envelope, you will actually be able to see two very nice mansions.
I’ve made a few mistakes, I realized too late, with the language [Specifically some of the British terms.] But that’s also something I try to consider while working on them. [ That and sometimes creating real copies of things like the Christmas cards.]
After that, it’s about developing a change in spelling, penmanship, sentence structure, even the art styles. It’s something that constantly changes as they grow up, and I hope to be able to express that as things go along.